Title

Authors

Document Type

Journal Article

Role

author

Standard Number

1058-5893

Journal Title

International Journal of Plant Sciences

Volume

173

Issue

6

First Page

596

Last Page

609

Publication Date

2012

Abstract

A hypothesized advantage of the building block of the angiosperm vascular network, the vessel, is often cited as a critical innovation that elevated the competitive abilities of early angiosperms above nonangiosperms during the Cretaceous. Here we synthesize recent discoveries on the hydraulic functions of living basal angiosperm lineages with evidence from the fossil record to trace the early evolutionary significance of vessels in the early ecophysiological radiation of angiosperms. Evidence from extant comparative biology and the Early Cretaceous fossil record of leaves and wood do not support the hypotheses that vessels improved drought tolerance of angiosperms, increased angiosperm's photosynthetic abilities, or provided an immediate leap in hydraulic capacity. Instead, later tuning of vessel structure for increased flow efficiency-in particular, by the evolution of simple perforation plates-enabled major increases in xylem hydraulic efficiency. --author-supplied description